Abstract:
Most of the ESA archive has been acquired and processed at receiving stations in Fucino (Italy), Kiruna (Sweden) and Maspalomas (Gran Canaria, Spain). However, the archive contains also a substantial number of data acquired and processed by receiving stations elsewhere (e.g. the US, Brasil, Canada, ect.).

The system corrected data ... contains MSS data radiometrically and geometrically corrected relative to the four MSS spectral bands covering on full WRS scene. Radiometric and geometric corrections are applied in sequence and the quality standards are expressed by combined radiometric and geometric corrected data quality standards.

RADIOMETRIC CORRECTIONS Each pixel's radiometric value is processed through a look-up table, generated with one of the following methods:

* Relative radiometric corrections method (statistical): this method performs the statistical equalisation for the different detectors of the same band. * Absolute in flight radiometric calibration: this method utilizes the on-board calibration wedge data to determine the absolute radiometric calibration gains and offsets. * Relative and absolute radiometric calibration method: this process is a combination of the above methods.

GEOMETRIC CORRECTIONS The MSS geometric corrections are based on the generation of three geometric correction tables which group the different geometric error sources and model:

Landsat full scene of imagery data correspond to an effective ground coverage area of approximately 185 km wide by 185 km in along-track direction for Landsat 1, 2, 3 and 185 x 170 for Landsat 4 and 5. A standard full scene is nominally centred on the intersection between a path and row (the actual image centre can vary by up to 20 km). For a floating full scene the placement along the path is chosen by the customer. The centre point of the floating full scene is defined by the path number and the required latitude. A full image is composed of 6920 pixels x 5760 lines and each band requires 40 Mbytes of storage space.